1. Field of the Invention
The present invention relates to connection systems for barge-tug connections in which a tug pushes a notched barge allowing relative vertical movement therebetween. More particularly, the present invention relates to a fender system for use between the barge and the tug to buffer forces therebetween, and to a connection and tensioning coupling device for the "pushing lines" which connect notched barges and tugs together preventing separation in adverse sea conditions while allowing relative movement between the tug and the barge, and further allowing easy, quick release of the pushing lines in emergencies without human intervention on deck.
2. General Background
It is known in the marine art to secure a tug in the notch of a V-notched barge by using pushing lines.
It is also known to form connections both fixed and moving between the tug and the barge at the tug bow.
When connecting a tug and V-notched barge, pushing lines are usually firstly connected. One end of a heavy cable, generally a wire rope, is secured with a shackle to the transom of the barge on each side. The other end of this cable, called the pushing line, runs over a large sheave pinned on the aft deck of the tug, close to the bulwark, and is then secured either to the deck of the ship or to the towing winch, sometimes through some kind of device giving some elasticity to the assembly.
Generally all systems are built on these present principles and differ only by their components. Most of these prior art systems have the same drawbacks. The pushing lines at sea are taut and slack alternatively, due to relative motions of the tug and barge, and snap by snatching when the sea deteriorates. The handling of those lines is very clumsy and there is generally no safe emergency release system.
Rubber tires, rigid connections, and complex "pinching" arrangements are used to space the barge-tug longitudinally, usually at the bow of the tug. Those systems of the prior art, although in use for many years, have not been greatly improved since the tugs were pushing only in relatively good weather.
The sizes of tugs and barges are now increasing sensibly as well as the necessity to keep on pushing in adverse conditions. Some recent technological improvements on the fender system of the tug allow the tug to stay in the barge up to fifteen (15) foot seas and there is a demand for improved pushing lines. An increase in the size of the actual system becomes a problem in that large systems are impossible to handle by the crew members and too expensive.
U.S. Pat. No. 4,168,672 issued to Fletcher discloses an apparatus for transmission of thrust from the bow of a tug secured in the bottomless recessed well of a barge. Transmitting means is mounted to the bow of the tug to a retaining means which is mounted to the stern of the barge and an ajustable coupling means is mounted to the tug and barge proximity of the thrust transmitting means and complementary retaining means. The apparatus may include calbes for connecting the tug to the barge for maintaining longitudinal alignment and a number of resilient bumpers mounted to the bow of the tug to absorb collision shock between the two vessels.
U.S. Pat. No. 4,148,270 issued to Bludworth discloses an apparatus for releasably coupling an articulated ship, particularly a tug-barge combination, by use of a coupling arrangement permitting both rigid and flexible interconnection. One vessel is provided with opposed bearing surfaces which are secured to the gripping members of the second vessel. The barge partially accepts the tug in a bottomless notch in its stern.
U.S. Pat. No. 4,041,888 issued to Hooper, et al, discloses a thrust transmitting means for a tug and barge without mechanical coupling. A deep bottomless V-notch is provided at the stern of the barge to receive the bow of the tug. The bow of the tug has a thrust exerting member which is adapted to mate thrust receiving means on the barge at different relative drafts of the two vessels. Automatic lubrication is provided to the mating system.
A prior U.S. Pat. No. 4,031,843 issued to applicant herein, Jean Paul Colin, discloses a tug-barge interconnection where the barge has a longitudinal groove at the stern of the barge having an inverted T-form in transverse cross-section which is adapted to receive the tug, which has a rigid thrust transmitting member attached thereto. The vessels are interconnected by hydraulic compression members combined with pressure accumulators. Inflatable cushions are interposed between the barge and tug surfaces.
U.S. Pat. No. 4,023,519 issued to Harms discloses an apparatus for coupling a tug in a barge. The apparatus comprises coupling means in the stern of the barge and at the bow of the tug to allow relative movement of the vessels about a vertical axis. Elongated flexible connectors are provided between the vessels, one on each side. The tug can act as a rudder for steering the barge.
U.S. Pat. No. 4,026,234 issued to Zbilut, et al, discloses a device for coupling a barge to a tug for sea transportation, the barge having a stern portion with a bottomless, V-notch or nest and the tug having a bow to mate with such nest. The coupling device includes a system of guiding rollers which are mounted on the wings of the nest of the barge including shock absorbers and hydraulic power devices. Cables are passed over the rollers and fixed to the deck of the tug. The device has self-adjusting qualities securing both constant position of the tug relative to the barge and a constant pressure of the tug against the barge both in pushing.
U.S. Pat. No. 4,013,032 issued to Bludworth discloses an articulated ship comprising a cargo vessel and a powered vessel. The cargo vessel has a bottomless, V-notch at its stern end for receiving a portion of the powered vessel. Three individual locking means are provided for rigidly coupling the two vessels together for instantaneous engagement and disengagement. The locking means permit a multiplicity of relative draft engagements of the two vessels.
U.S. Pat. No. 4,000,714 issued to Jean Paul Colin (applicant herein), discloses a system for interconnecting barges and tugs in which the barge has a longitudinal grooved recess which is an inverted T-section in cross-section into which the bow of the tug can adapt itself with clearance when the tug and barge are brought together. They are secured to each other by thrust transmitting and receiving members.
U.S. Pat. No. 3,962,983 issued to Ono discloses a connecting structure for an oceangoing push barge. The bow of a powered pusher-boat is connected to the stern of a powerless barge in a recessed or notched, bottomless portion formed at the stern of the barge. Projecting connecting pins are provided at positions near the center part of and on both sides of the bow of the pusher-boat. These are inserted in connecting pin receiving ports formed at corresponding positions in the recess of the barge to unify the vessels into a single navigable vessel.
U.S. Pat. No. 3,954,078 issued to Garcia discloses a method of connecting adjacent units of a barge two with interlocking connectors between which unit ends deflated cushions are placed in expandable enclosures for preventing friction between the cushions and the tow units when they are later inflated.
U.S. Pat. No. 3,949,699 issued to Heese discloses a method and apparatus for connecting two vessels such as a tug and barge to form a composite vessel. It uses a hydraulically powered apparatus to extend a shaft from the vessel in it on toward the other vessel which has an apparatus to capture the extended shaft.
U.S. Pat. No. 3,935,831 issued to Yamaguchi discloses an apparatus for connecting a tug and a barge in which the bow of the tug is received in a bottomless, notched stern portion of the barge. Movable connecting pins are mounted on both sides of the bow of the tug and are inserted into vertical channels formed within the notch of the barge.
U.S. Pat. No. 3,922,993 issued to Bludworth discloses a barge with a bottomless notch in its stern for receiving the bow of a tug with bumpers therebetween to prevent relative yawing of the two vessels. A coupling apparatus is provided to permit vertical pivoting of the two vessels about the point of couplings.
U.S. Pat. No. 3,910,219 issued to Ono discloses a connecting structure for tugs and barges wherein the stern of the barge is notched and bottomless receiving the bow of a tug. The front and sides of the portion of the tug which is received into the notch of the barge are provided with connecting pins protruding from the tug which are accepted in vertical receiving ports in the notch of the stern.
U.S. Pat. No. 3,892,196 issued to Swoboda discloses a tug-barge connecting system wherein hook-shaped latching members are provided on both the tug and barge for coupling the tug to the barge.
U.S. Pat. No. 3,892,195 issued to Janssen discloses a tug-barge coupling system in which tension coupling elements are connected to the barge and extend along the barge laterally of the tug and being connected thereto.
U.S. Pat. No. 4,073,217 issued to Jean Paul Colin (applicant herein), discloses a hydraulically or pneumatically controlled device for locking a piston in the bore of its cylinder at any point of its stroke. It comprises a piston and mounted thereon fluid tight seals, a series of wedges, and annular jacks incorporated in the piston.
U.S. Pat. No. 4,072,122 to Balston discloses a hydropneumatic device which secures and releases a mooring or towing hawser to a vessel.
U.S. Pat. No. 4,048,941 issued to Legnos discloses a barge with a bottomless notched stern for receiving the bow of a tug for an integrated vessel capable of use on the high seas. The tug is formed to securedly fit into the notch of the barge to prevent lateral movement.
3. General Discussion of the Present Invention
The present invention solves the prior art problems and shortcomings by providing a barge-tug connection, tensioning, and hydraulic spacing apparatus which allows relative movement between the tug and the barge in adverse sea conditions with a snapping of the pushing line being prevented. Further, the system of the present invention provides a reduced stress on the aft deck of the tug, consequently reducing the price of the tug. The present invention further provides a fast, efficient and safe emergency release system which can be operated without personnel on deck. The present invention also provides an apparatus which facilitates easy connection of the pushing lines and avoids the handling during connection of the pushing apparatus by deckhands.
The present invention provides a barge and tug connection apparatus with a barge having a V-notched portion connecting to a tug, the tug allowed to pitch and heave within the barge notch. At least one elongated elastic pushing line having barge and tug end portions is provided, with connections being perfected at the respective end portions to the barge and to the tug. A pre-stressing member mounted in the preferred embodiment on the tug stretches the pushing line uniformly along its length between the tug and the barge, the pushing line being unidirectional and being entirely disposed during operation between the tug and the barge, at the end connection portions.
A quick release system allows quick disconnection in, for example, emergency situations.
An improved fender system provides a plurality of hydraulically actuated pads on the tug to transmit forces between the tug and barge, absorbing shock and preventing damage. The pads act as fenders positioned away from the tug and bear against towers on the barge having bearing surfaces receptive of the pads. An associated hydraulic system pressurizes the pads to a desired pressure with the pad wear surface, with the pads having an indexing spring assembly which registers the pad at a desired normal position absent pressurization or contact with the barge.
The pre-stressing member can be a powered lever movably attached to the tug aft deck (see FIGS. 4 and 6). The pushing line lever connection can be a hook and eyelet connection with the lever providing a hook and the pushing line having an eyelet. Other suitable temporary connections such as a claw/ball or removable pin could be used.
The quick release system in the preferred embodiment is a slot in the tug bulwark, with the lever moving through the slot effecting a disengagement with the larger eyelet, the eyelet being unable to push through the slot.
The lever could be powered, for example, hydraulically by using a hydraulic cylinder affixed to the lever and to the tug deck. An alternate embodiment provides a movable powered carriage with an outboard projecting hook (see FIG. 7), while still another embodiment provides the hook portion directly affixed to the hydraulically powered cylinder (see FIGS. 10 and 11).
An improved articulated bow fender maintains horizontal spacing of the tug-barge in a longitudinal direction. The bow fender provides a first generally vertical coupling plate affixed to the tug bow with a second coupling plate attached thereto in a movable fashion which allows relative movement between the plates. The plates are preferably vertically disposed and are preferably connected by a "pinned" connection which allows pivoted relative movement. A plastic generally flat face-plate mounted on the second moving coupling plate bears against a provided flat surface of the barge. Both bearing surfaces are generally vertical and flat, and extending laterally a distance in the port-starboard lateral direction. Pressure applied by the pushing lines and the tug urge the tug and barge bearing surfaces together during operation. The plastic surface which can be provided, for example, on the second coupling plate lessens friction and wear between the tug and barge.
It is thus an object of the present invention to provide a V-notched barge and tug connection system allowing relative movement between the barge and tug even in heavy seas.
It is another object of the present invention to provide a v-notched barge and tug connection system which reduces stresses transmitted to the pushing rig.
Another object of the present invention is to provide an improved fender system for transmitting forces between the barge and tug responsive to relative movement therebetween.
Another object of the present invention is to provide a fender system for use between tug and V-notched barge towing arrangements wherein the side fenders have laterally movable fender surfaces which can be retracted for insertion or removal of the tug, and actuated to expand with the wear surface during operation being forced into pressured contact with the barge.
Another object of the present invention is to provide a resilient fender arrangement for V-notched barge and tug connections which absorbs shock between the tug and barge generated during operation.
Another object of the present invention is to provide a V-notched barge and tug connection system wherein the connection is safely made without direct human intervention in the vicinity of the stressed pushing lines.
Another object of the present invention is to provide a V-notched barge and tug connection system which is quickly, easily, and safely disengaged during, for example, emergency situations.
Still another object of the present invention is to provide a V-notched barge and tug connection system which eliminates the chance of pushing lines becoming slack during the pushing operation, even during excessive relative movement between the barge and tug as occurs in heavy seas.